Scooterotica

Scooterist pals,

The Pinasco 215 kit seems to be running in nicely but I'm stuck on jetting. I didn't plug chop ....yet. Might not have to since I think I'm close.

Lets start from right now: Crank is stock 57mm, gearing stock. Carb is a Del 'Orto 24/24. The 7mm/5mm hole "air hole mod" in the air cleaner was done this evening. Sito+ exhaust.
Current jetting: Main stack: 160/BE4/130. Slow running: 55-160.

Starts and idles nicely. Pulls like a mutha (well to me) from 0-50 and then tapers off. Nice and linear power delivery in that range. I got up to 55 and left it as I'm only at about 250 miles on the cylinder. Ambient temp is 45F/7C out tonight.

Lets go back in time. Same everything but 125 main jet, no air hole mod in air filter. Pulled nicely (not as amazing as tonight) up through about 40 mph then would get up to 60 MPH (very limited time!) but no more pull and about 1/4 left over. Plug was pale on the whiter side so trying to limit shenanigans like going over 45 for extended periods of time. Temps were about 70 to upper 80's (Fahrenheit).

Next I plop in a 130 main jet, nothing else. Next morning 0-50 is shot to hell. Sputtery and jumpy and when it hits 60 smooths out and I have about 1/4 throttle left it has some decent pull left over. Problem solved on the top end. Plug starts to get some dark deposits on the back of the side electrode, rest of the plug still looks pale.

Well now that its back to cooler temps by about 30-40 deg the lower end is okay (about like stock pull, no sputtering) so I'm convinced the lower range suffered from being rich. Top end now horrible. Can't even get past 55 (granted, it was dam windy that day. Like gusts up to 50 mph w/ a steady 40).

Tonight with more air being drawn in it goes like I expect it would. Might even have a decent top speed but I'm afraid to push it. The only thing that's a mystery now is plug color (didn't pull it as it's time to sleep) and that nice upper end pull I had on the warmer day w/o the air mod seems missing. If I can cruise at 60-65 I'll be happy enough.

My first rally of the year is coming up this weekend. I want to make sure I have my top end and fun acceleration. Would you folks suggest I get a BE3 mixer to play with? I currently have the following main jets to try: 122, 125, 130, 135. Should I get a different air corrector and slow running jet?

I'll give you my plug color results tomorrow. If you have suggestions I would really really appreciate some of your vast knowledge of jetting. Thanks!

You might benifit from experimenting with a 140 air corrector. The air corrector controls the rate at which the fuel flows not the volume but can still be useful for up jetting.
I would have started with the BE3 mixer so try that first.
Also experiment with removing the hose that connects the carb box to the frame or at least unhooking it from the frame.
The drilling of the filter doesn't always have a benificial effect.
Don't rule out compression causing your jetting problems especially with the Pinasco. Too much compresion will cause you to run richer jetting but it won't always be predictable and will change as the bike gets hotter or ambient temps change. Its not a perfect fix but Edens trick of running a short reach plug will reduce compresion a little to prove or disprove this being a problem. If it does you will need to remove material from the head.

Thanks Diablo. Apparently the BE3 is a hot item right now in the midwest. Out of stock at three places I called. I have a BE5 coming for the hell of it thanks to ramblings from the Scooterworks vaunted technician. I really miss Daniel Rieke at Sportique in Denver. He knew his scooters and no BS. I called Sportique today and a nearly asthmatic smoker chick answered (no offense lady, Phillip Morris is to blame) and was taken aback my by highly technical talk about a couple of brass tubes with holes in 'em. Told me they'd call back. No call. Just like Scooterjerks I mean Scooterworks in Chicago.

I had to call Scooterworks after leaving a message hours before and of course I was too late to hit today's ship date. Cost was about 16 bucks. For one BE5 air mixer tube and "Priority" shipping which might make it by Thursday, the day before I leave for my first Rally. Ugh.

Need a shop that delivers. Need a shop that knows 2-stroke Vespas. Anyhow, my next pathetic grasp at sanity was to plop in the 135 main. Will be interesting to see how it runs tomorrow night. Have it up on jacks to change the tires, clean brake shoes and some smaller, non important (to get to a rally) bits. Hope to update you here soon.

Happy aside: sure is nice right now having powerful acclereration. Hope to shock cars once again.

Current setup: 160/BE4/135 (latest) working very well. Haven't checked plug color but this could be it. I will be getting a BE3 mixer and 140 A/C when I can track them down.

I plan on having the stock Pinasco head skimmed about 1mm in a month or two. The jetting fun will start all over again (possibly timing as well).

I still haven't put the timing light on or used the dial gauge and all that yet. Just moved the stator plate back a bit w/ eyeball and guessing. No pinging so far but we have another 30F to go when we get into our high temps and I'm sure that will make a difference on all I've accomplished so far.

I'll update you all on my current plug color and jetting as I move things around. So far I'm experiencing the best overall power and smooth acceleration throughout the entire range.